Surface grinder



C. KNWLES.

SURFACE GRINDER.

APPLICATION mw reu.

ifm. m

Patented Aug 8, 1922.

8 SHEETS-SHEET l fm umlloz n///f /l Remmm C. KNOWLES,

SURFACE GRINDEH.

APPLICATION FILED FEB.7.192I,

Patented Aun". 8, 1922.

8 SHEETS man t r\| I HQE I- C. KNUWLES.

SURFACE GRINDER.

APPLICATION HLED FEB.7,1921.

Patented Aug. 8, 1922.

8 SHEETS-SHEEI` 3.

C. KNUWLES.

`SURFACE GRINDER. APPLfcA'rmN FILED FEB. 7. 1921.

FIG.

14% (Juve/11 lozfI C. KNOWLES.

SURFACE GHNDER. APPLICATION mw fEB.7

lil

l El

C. KNOWLES.

SURFACE GRINDER.

APPLICATION FILED FEB. I, IIIzI.

IAQIHG@ @2 SI1 waaien MKM/mf C. KNUWLES,

SURFACE (MINDER.

APPUCAUON mw FHL/.1921.

PatfnedAug. 8, 1929.

lira sae,

oa' e 1.1. nNowLrs, or

HARTFORD, CONNECTICUT,

naar or.

AssrGNoR 'ro PRATT a WHITNEY COMPANY, 0F NEW-YORK, N. Y., A CORPORATION 0F NEW JERSEY.

SURFACE GRINDEB.

igienica.

, Application led February 7, 1921.

To all/whom t may concer/n.: V

Be it known that I, CARROLL KNoWLEs, a citizen of the United States, residing at of Hartford and State of improvements in Surface Grinders, of which the following is a specifil driving trol of the to be ground ma cation. j j

This invention relates to surface grinders and especially to a grinder of this type having a rotating table on which the articles y bj'e grouped.

Une of the objects ofthe-present invention is to improve .the construction of large size surface grinders land particularly to adapt them for rapid and accurate work on a plurality of pieces simultaneously,` one of the features of the invention being, that the motor for driving the abrasive wheel is yindependent lof the motor for rotating the table andv operating the The 'wheel driving motor isflocated 4oni the upper portions of the 'grinderjframe and.

ing the wheel head, the means is connected to the wheel head through bevel range of adjustment .is possible for the wheel, and-inaccuracies of alignment of the j shafts are compensated.

. Another object of the invention is to provide an improved automaticl feed 'for the abrasive wheel, supplementary to the manual feed, permitting a ine adjustment-and conthe-work during the grinding-operation.

ing mechanism one of the motors whereby the y be quickly adjusted vertically when the finished articles are .to'be removed, or during the resetting of the machine-.for operation on different types of articles. Also.,

it is an object of the invention to improve v per .revolution of the' table.

lSpecification of Letters Patent.

feed mechanism. l

movements of the 'wheeljtoward 1n Another object of the invention-is tov pro-y vide an improved rapid elevating and lowerfor the wheel operated by wheel mfa'fyy Patented Aug. 8, i922.

serial Na. 448,298. 'With these and other objects in view, my

invention consists in the features of construction and operation set forth in the following specification and rillustrated in the Y accompanying drawings hereof.

In the accompanying drawings annexed hereto and forming a part of this specification, I have shown my invention embodied 1n one type'of machine but it will be unde rstood that the invention can be otherwisfe embodied and that the. drawings are not to be construed vas defining or limiting the scope of the invention, the claims appended at the end of the specification being drawn to define` the scope of the present inventlon.

In the drawings: v

Figure 1 is a side elevationy of thecomplete machine. j

Fig. 2- is a rear elevation of the complete machine.

tion, showing the Wheel head, the table and a part of the wheel feeding mechanism.

Fig. 5 is a side view of the parts shown in.

gig'. 6 is a' side elevation of forming a part partly in 'secn `8@ a -part of the table rotating mechanism and wheell feedv mechanism.

same parts shown the rear. j y

Fig. 8 is a plan view of the change speed mechanism for rotating the table, parts being broken away to more clearly show the construction.

Fig. 9 is a sectional viewv of the parts shown in Fig. 8.

Fig.` l0 is a sectional the mechanism for rapidly elevating and lowering the Wheel head. Fig. 11 is a part of the feed mechanism for kslowly feeding the wheel toward the wor in Fig. 6 viewed from view in elevation of ig. 7 is an elevation 'in section of theelo Fig. 12 is a' on line 12--12 nection between wheel feeding in screw.

' ig. 13 'is a sectional view taken' on line 13-13 of Fig. 12 showing the operating means for the rapid traverse movement ofplan view in section taken of F ig. 3 showing the conthe driving spindle for the means and the wheel elevatsupported thereon and movable in a vertical plane; third, a table rotatably mounted in the base and in operative position relative to the wheel; fourth, change speed-mechanism for rotating the table; fifth, power elevating and depressing mechanism for the abrasive wheel; and sixth, mechanism. for slowly feeding the wheel downward during the operation of grinding either by hand or ower.

eferring' more particularlyto the draw-l ings, in 'Figs 1 and 2 the main outline of vthe princlpal elements is shown. These .principal parts comprise a base 10 on which is mounted a column 11, and, near the for# .ward end ofl the base. 10, a work supporting table 12 is suitably mounted and adapted to rotate in ahorizontal plane.

The column 11 is angularly adjustable on base 10 by means of adjusting screws shown `the table 12.

generally at`13. These permit a limited angular movement or tilting of the column 11 to permit operation on slightly'concave ,or convexjwork. The column ,'11 is surfaced `near. its upper extremity to form a supporting sur ace 14 for a vmotor 15.. yThe shaft 16 for the motor 15 is connected through'a flexible connection 17 with gear 18 forming one of a pair of bevel gears. The opposite gear of the pair, shown at 19, is attached to a vertical shaft 20. By means of shaft 20 the abrasive wheel 21 is rotated at a high rate of speed. The connections andv feed mechanism lfor this abrasive wheel will be described more in detail further on. Suiiice it to state at the 'present that means are provided forv raising and lowering the abrasive wheel in relation to and while held substantially parallel with thel surface of Tn order to rotate the table 12 and also to elevateand depress the abrasive Wheel 21 both for adjustment and for feeding, a separate motor is provided. This is shown at axis.

lineages 25 andis preferably mounted on assuitably' surfaced portion onV the rear face of the column 11. The armature shaft 26 of this motor drives a belt 27 which passes around driving pulley 28 for the tabler rotating mechanism presently to be more fully described. This armature shaft 26 is also provided with a pulley overwhich a belt 28a passes. Belt 28l passes around pulleys with- 1n the column by means ofwhich the means for rapidly elevating the wheel is operated.

Coming now, to a` detailed description of the `principal parts outlined above, the construction of the column, the wheel head and the wheel rotating mechanism will first be more specifically described. This construction is shown in Figs. 3 and 12. On suitable guideways 35 provided on the front vertical face of the column 11 a tool carriage or head 36 is adapted to slide'along a vertical This head 36 provides a support and guide for spindle 37 to which the wheel 21 1s directly fastened. The head 36 issuitablyfcounterwcighted by means of a heavy weight 38 within the column 11 which 'is connected to the head 36 by meansv of a chain 39 passing over` idlers 40 and 41. For convenience and accuracy in operation of the machine, T prefer to over-counterwcightthe head, that is, to make the weight 38 considerably heavier than the combined weight of the head 36, the wheel 21, and the other vertically movable parts operating therewith.4 'This 'provides acontinually acting upwardv thrust Vto the tool head and prevents a` tendency for the wheel 21'to low the position determined by the feed mechanism. In order to protect the guideways` 351'on the column 11 from gritand water, I preferably provide a flexible curtain 42 adjacent these ways. This is attached at lone end to the head 36 as shown at 43 and passes over suitable rods or rollers 44 and 45 providedy in the column 11, and is held in stretched condition length by a weight 46 depending from its opposite end.

. To elevate or depress the wheel .21 and the head 36 a vertical elevating screw 50 is prothroughout its- 100, drop slightly bevided. This is rotatably-mounted in the column 11 alon a vertical axis and is provided with a bal thrust 51 near its lowerend to take the upward thrust of the Wheel head 36 and also to decrease friction. It will be apparent that as the counterweighty 38 is heavier than the head, there is a ycontinually acting upward thrust of this screw 50 on the thrust bearing 51. Near the lower end of the screw 50 'and preferably'belovv the thrust bearing 51 is a Worm wheel 52 meshing with a Worm 53 on a shaft 54 by means of which' the screw 50 36 and wheel 21.

may be rotated byvr mechanism to raise or lower the wheel head.

. The tool head 36 has va projection 56 on 166 standing ring 73 extending from its upper c 4 20 and .having a plurality'of pins 87 dependi integree j its rearward surface which is suitably bored to contain a nut 57. rlhe nut is rigidly fastened to the carriage head 36 by suitable screws 58 so that rotation of the screw 5.0 serves to traverse the nut 57 along the screw 50 and consequently moves head 36 vertically upward or downward.

At its forward and upward portion the column 11 is suitably finished to provide a supporting surface 60 for a suitable housing 61. Within this housing 61 are located the bevel gears 18 and 19 previously referred to which act as driving members-for the spindle 37 rlhe housing 61 also contains bearings for the continuation of shaft 16, which bearings are in the formof ball bearings 65 and 66.` Bearings, such as shown at 67 and 68, are also provided for the shaft 20 previously referred to. l also preferably provide a sleeve .69 surrounding the shaft 20 to which the inner rings of the ball bearings 67 and 68 are fastened. This sleeve 69 is keyed to the shaft 20 as shown, bevel gear 19 is also keyed or otherwise fastened directly to this sleeve.

Coming now to a description of the wheel spindle 37 andoparts associated therewith, it will be seen that the wheel 21 is mounted centrally in the head 36 on the spindle 37 which is rotatably mounted in the head 36 b means of thrust bearings 70 and 71. Vghile in use the thrust is at all times upward on the spindle 37 so that the thrust bearings 70 and 71 are placed vas shown in the Figure 3, the major portion o the thrust being taken by the lower and larger bearing 70. The upper thrust bear- 'in 71 serves to take up the weight of the spindle 37 The spring pressed sleeve 71a surrounding the spindle 37 is constantly urged upward against the outer ring o f the thrust bearing 71 and thus holds the spindle 37 and wheel 21 in their upper-most position. Between the wheel 21 l flange or face plate 72- secured to the lower end of spindle 37 and by means of wheel 21 is rigidly secured tothe spindle 37. This flange 72 is provided with an upforms an annular groove be continually supplied to the `inside of the surface which to which water may and from there admitted wheely 21.l Water may be supplied to this suitable source, not' groove 74 from any shown, and may be admitted to the inside of the wheel `21 through a channel 75 extending from the groove or ring 74 to the lowery surface of the flange 72. Within the upstanding ring 73 is a small oil reservoir 76 to which oil may be supplied-.through a suit-v able inlet 77. 'lhe flange or face plate 72 is also provided with baffles or veins 78 within the oil reservoir 76 tending to force or throw the lubricating oil upward into the oil-*circulating channels (not shown),

and the spindle 37v isa y which the Surrounding thewheel 21 and depending from the lower portion of the head 36 are annular rings 79 andv 80 preferably adjustably mounted relatively to each other so that one may telescope within the other. The upper one of these/rings 79 is made fast toa disk 81 rigidly secured to the head 36. By means of screws 82 the rings 79 and 80 may be held in any adjusted position relative to yeach other. The screws 82 pass through oblique slots 83 cut into the ring 79 as shown in Figs. l and 5 so that the guard ring 80 may be extended tol enclose the major portion of the wheel 21.

ln addition .to the rings 79 and 80 attached to and moving vertically with the Wheel head 36 and completely surrounding the wheel 21 are curved plates 84 and 85 placed in rear of the rings 79 and 80. Plate- 85 is suitably fastened to thev column 11 by screws 86 preferthe Wheel head slide as shown in Fig. 12.

lPlate 84 is fastened in any suitable way (not ably extending into the straps or gibs for the bevel gear 19 and the wheel spindle 37 the following mechf anism is provided. Between the shaft 20 and the spindle 37 a flexible connection 86 is provided so that the spindle 37 and sha-ft 20 are not necessarily adjusted absolutelyr into alignment with each other and the .flexible connection 86 thus serves to allow 'slight variations from alignment between these two members. The spindle 37 is also suitably bored as shown at 85 so that theshaft 20 may telescope within spindle 37. j

The flexible connection which l spindle`37 and to permit slight adjustments of alignment comprisesthe'part 86 in the form of a flange suitably splined to the shaft Vflexible connection, particularly between the and the belt 90, slight vertical pins`87 and 89 the spindle 37 and shaft 20 movement of prefer-- ably use to `permit vertical movement of the' ll@ l f in turn rotates the worm wheel 52 and the may be taken up. Thus, while rotate in opposite directions. Each pulleys 92 and 93 is provided with a fric-' tional surface 94 concentric witheach pul-l ley which is adapted to contactwith, and' feeding the Wheel 2l toward the Work,` that is, during the grinding operation, the vertical movement may occur between the belt 90 and pins 87 and 89 rather than between the member 86 and shaft 20. f

Coming now to a description ofthe mechanism for rapidly raising and lowering the Wheel 21, the screw is used to elevateand depress the wheelhead 36 during its adjustf ment for different sizes of work and also face of column 11 passes around two pulleys 92 andV 93 mounted adjacent each other .and which are rotatably mounted on fixed studs 92a and 93a. The belt 281 passes around the;

pulleys 92 and 93 inthe manner indicated in Figs. 3 vand 13 so that ',thetwo frictionally drive a pulley 95. The pulley 95 is mounted eccentrically on one end of a short shaft 96 asv shown in Fig. 10 'so that oscillation of shaft 96 forces the pulleyl 95 against one or the other ofthe frictional driving surfaces 94 with which the pulleys 92 and 93 are provided. By means of a pin 97 inserted in,` the forward face ofthe pulley 95 engaging a slot 98 provided in a-liange `99 fastened shaft, is rotated. The direction of rotation of shaft 54 is dependent'upon which of pulleys 92 or. 93 is in engagement with pulley 95. The rotation of vner therefore rotates the worin 53 which is` shaft 54 in this mandirectly mounted on the shaft 54 and which l,screw 50, thus raising orlowering the Wheel head 36 relative to table 12.v-

To oscillate the 'shaft 96 and thus cause thes'crew 50 to be rapidly rotatedin either direction I provide a rod 100 extending toI one side of the machine 4and having at its inner end a segmental gear 101 connected withl a correspond-ing segmental gear 102 pinned to the shaft 96. A handle 103, A(see Figs. 1 and 5), conveniently mounted on the outer end of the` rod'100 provides means for oscillating it thus controlling the operation of yrapidly raising or lowering the Wheel head 36. v

1n order to prevent ldamage to the machine -or any of its parts by running the wheel head 36 so that the wheel 21 comes into contact with the table 12 or moves beyond its proper limit 1 provide adjustable dogs 110 pulleysl of the either limit in Fig. 11,'. .At theend of to one endof the shaft 54 this ,i

'shaft 100 by sliding to fand, through a vand 111 (see AFig. 5') mounted at one side of the wheel head 36. The upper dog 110 may be adjusted accuratelyI andeasilyby adjusta ing screw 112. Two of these dogs are preferably used,foneto 'limitthe upper movement of the wheel head and the other its lowermost movement. Each of the dogs 110 and 111 is provided with a cam surface. An oscillating lever 115, preferably as shown in Fig. 5, is pivotally mounted on the side of the column 11 and is provided at its upper endl with a lug 116 adapted to contact with either of the dogs 110 or 111 previously described. As soon 'asthis lug v116 comesl into contact with one or the other of the cam surfaces on the dogs 110 or'111 the oscillating lever 115 is moved to vertical orl midway position as shownk in Fig. 5. Movement of ythe lever 115 to this position from either of lts-oblique positions moves a bar 117 con,-

nected lto the lowerpend of the lever 115 and having,v at 'one end, a

numberof rack 'teeth 118. n These rack teeth'118, mesh with a segmental gear 119v fastened on the, rod 100a so that as soon as'the'wheelxhead 36 reaches y j of itsjrnovement the lever V115 is oscillatedto itsjmid position. This oscillates ythe short shaft-96 a part of a revolution and removes the pulley 95 'from contactwith one of the' driving pulleys 9 2 or 93 so that rotation ofthe worm53 is stopped.

To permit the shaft roo'ywhich is usedI 'during the feeding movementsv of the ywheel l .-21 to bedisconnectedy from the shaft 54 to` permit rapid traverse of the* wheel 21, I preferably use the formof Aconnection shown vshaft 54, a 'small flange. 120 1s secured having a single slot 121 extending` radially therein'. On the shaft/ isslidablymounted a Vmember 122` having a single projection 123 adapted to enter;l the slot 121. Member 122 is splined toshaft 100 and'may be moved along the 103, a short distance.v Movement of shaft 100a axially moves member124 pinned therepart -of member 124 engaging a circular groove fin the member 122 moves the projection 123 into or out of engagement with fiange `120 on shaft 54. By this means the handle'103 may be utilized tocontrol the rapid traversemovements of the" wheel head 36y and also may beutilized toy-connect and disconnect both the power andA hand` feeding mechanism;I For1convenience the member 124 fastened tothe shaft 100,1 may be provided with'the seg'- mental gear19 previously referred to.

The supporting and rotating mechanism for the table will-now bel described.

The table 12 is rotatably mounted in the base 10 about a central projection 125 formed on the lower surface of the'table 12l and `adapted to lit a bearing 126 formed, directly in the base 10. j'

the shaft 100n and handle f ist (not shown) may be surface of'this table means may be protable 12 and embedded in a suitable insulating ring 128. From these slip rings 12,7 wires may be provided extending to a magnetic chuck provided on the upper'surface of table 12 if found desirable. Also secured on the lower surface of the table 12 is a gear 130. This in the form shown is an annular ring, the gearv teeth being on its outer periphery. This gear 130 depends from the lower surface of the table 12 and is suitably secured in any convenient way centrally about l"the projection 125. The gear 130 forms the bearing mea-ns for supporting the table 12 and the means for `rotating it which means will now be described.

The motor 25, as previously stated, is provided with a belt 27 passing over suitable pulleys 27a, and extending forwardly centrally of the base 10 and around the pulley 28. Thisiis shown clearly in Figs. 1 and 2. The pulley 28 is fastened to a shaft 131 which forms the main driving shaft for the table rotating mechanism. This vmain shaft 131 is'provided with a main friction clutch 131"i formed of disks 132 and 133, alternate disks being attached respectively to the shaft 131 and a shaft 135 in alignment therewith. This clutch 1313L is operated by the axial movement of the clutch member 136 which may conveniently be controlled by a yoke 137 surrounding the clutch member 136 and operated by a lever arm 138 to which a pedal 139 is connected. As shown, -the,yoke member 137 and arm 138 are mounted on a short shaft 140. Normally the clutch member 136 is held in closed position so that the shaft 135 is rotated. This is accomplished by means of aspring 142 interposed between the clutch member 136 at one end and abutting at its outer end against a gear 143 keyed to shaft-1.135.

In order to provide aplurality of different speeds for rotating the table 12 I provide change speed mechanism between the shaft 135 and the gear 130 mounted on the table 12. This change gear mechanism comprises a pair of shafts 145 and146 parallel to each other and on which are mounted a plurality of gears of different. diameters. Shaft 145 is provided with a pair of gears 148 of different diametersmounted ixedly on the shaft and a air of sliding gears 150 also of different diameters. On the shaft 146 are mounted a pair of fixed gears 151 and a pair of sliding gears 152. As shown in Fig. 9 the gear 143 on shaft 135 is always in mesh with the larger of the gears 148 140 so that as the pedal 139 is and therefore drives the stant speed.' Shaft 146 is driven from shaft 145 at one of four speeds dependent upon the positions of sliding gears 150 and 152. To slide the gears 150 and 152 I provide a handle 155, movement of which slidesone or the other of a pair of short shafts 156 and 157 to which the gearengaging members 158 and 159 are attached. This serves to position the gears 150 and 152 so that one or the other of each .pair engages one ofthe xedly mounted gears on the other shaft. The speed change mechanism is such that but one pair of the sliding gears can be in mesh at the same time. This speed change mechanism is similar to well known forms of speed change gearing as, for instance, those used in automobile transmissions and therefore will not be more definitely described. As a part of the speedchange mechanism I pro--v vide an interlocking mechanism to prevent the change gears 150 and 152 beingchanged while the clutch members 132 and 133 are in driving contact. veniently be mountedon and oscillated with movement of the clutch lever 138 previouslymentioned. As shown, this interlock comprises an arm 160 secured to oscillating shaft depressed to release the clutch members 132 and 133, the arm 160 is raised sufficiently to disengage a plate 161 carried by arm 160 from notches 163 cut into the gear engaging and' shifting members 158 and 159. When the clutch members 132 and 133 are in driving position, the plate 161 engages the notches 163 and prevents movement of the sliding gears 150 and 152. As soon as the pedal 139 is depressed and clutch 131a released the plate or strip 161 is raised out of engagement from notches 163. The sliding gears 150 and 152 may then be moved by means of handle 155.

0n the shaft 146 is a driving bevel pinion 170 which drives a mating bevel gear 171 fastened to the lower end of vertical shaft 172. The shaft 172 is provided at its upper end with a pinion 173 meshing with the teeth of gear 130.

Preferably the handle 155 by means of which the positions of gears 150 and 152 are controlled is surrounded by a housing 175 in which is cut an opening an H. After moving the handle 155 to the left or right in slot 176 to engage it with either of the rods 156 or 157 it may be thrownV forward or rearward to move one or the other of gears 15() or 152 along its shaft; The handle 155 can engage but onel of the rods 156 and 157 at a time and cannot engage one of them until the other has been returned to its neutral position.

To feed the wheel 21 toward the table 12 during the grinding operation and particularly to vary the amount of feed and the limit of the feeding operation, the follow- 176 in the form of shaft 145 at con- This interlock may con- 50 any desired position in the 'arcuate slot 232.

- cross shaft 202.` Also mounted on shaft 202 is an eccentric or other form of cam 203 which is permanently fastened to shaft 202 1n anysuitable Way. The ratio between the gear 201 andthe worm or spiral gear 200 1s the same as the ratio between pinion 173 and the table driving gear 130 so that the eccentric 203 rotates once with each revolution of the table 12.

A shaft or rod 204 extending along the side of the base 10 is provided with a small roller 205 at one end which is close enough to the eccentric 203 to contact therewith thus moving the shaft 204 toward the right at each revolution of the eccentric 203. At the opposite end ofshaft 204 is a flexible coupling 205 at which point the shaft or rod 204 joins rodor shaft 206. Shaft 206 is attached to one arm of a bell crank 207, the other arm of which is attached to a vertical rod 208. .The pivot 207a about which the bell crank 207 oscillates is mounted on a small slide 209 suitably mounted in vertical ways 210 provided on the base 10. From this it will be seen that with rotation of the table 12, the eccentric 203 will be rotated and the vertical rod 208 reciprocated in timed relation thereto.

Rotatably mounted on the shaft 100 previously mentioned is an arm 225 which is pivotally attached as shown at 226 to the vertical rod 208, so that with reciprocations of the rod 208, the arm 225 is oscillated about the axis of shaft 100 and oscillates a pawl 227. The pawl 227 engages a ratchet wheel 228 fastened to shaft 100 and rotating therewith. By the action of the pawl 227, which is spring pressed toward the periphery ofthe ratchet wheel 228, the shaft 100 is very slowly rotated step by step by the vertical movements of rod 208.

To limit the oscillatory movement of the arm 225 and thus reduce the feedin action of pawl 227, I mount an adjusta le arm 230 about the axis of shaft 100 and adjustably fasten it by a clamping screw 231 at An abutment 235 on arm 225 takes up against arm 230, when the vertical rod 208 has completed a part of its downward movement. The amount of movement of arm 225 may therefore be varied by adjusting the position of arm 230 so that downward movement of rod 208 is stopped at one of its intermediate points.

Graduations -238 are provided adjacent the arcuate slot 232 which are' so calibrated that they indicate the amount of feed of the wheel 21 toward the table 12 for each movement of the arm 225 and therefore for each revolution of thel table 12. A spring 239' ments of the column l1. By means of the reach rod 240 extending' from a point on the column 11 adjacent the rod 100 `to the` slide 209, the position of slide 209 is slightly varied vertically with adjustments of the column 11 so that the upper limit of movement of the arm 225 is always the same and thus the feeding movement of the arm 225 is -the same from definite positions, determined by the position of the arm 230 for any adjustment of the column 11.

Adjacent the ratchet wheel 228 and rotatably mounted on shaft 100 is a dial 245, the periphery of which is yrovided with graduations 246r to indicate tlie feeding movement of the wheel 21 toward the'v table 12. The dial plate 245 normally rotates with the ratchet wheel 228 during the grinding operation by reason of lthe connection between them which comprises the followin parts. On the diallplate 245 is a lug 249 t rough which passes a stud 250 on a small block 251l rotatably carrying a s iral gear 252.

ounted on the same "mem er asthe gear 252 is a small knob 253 by means of which the gear 252 may be rotated and therefore the relative position of the wheel 228 and the dial 245 may be varied. ,During the preliminary adjustments of Wheel 21 whenit may be desirable to rotate the dial 245 freely relative to the ratchet wheel 228, the block 251 may be swung about so that the gear 252 is disengaged from the ratchet wheel 228.

The dial 245 is `provided with ay shield plate 254 which is fastened to the dial plate 245 and extends over a portionof the periphery of the ratchet wheel 228. As the feeding of the wheel 21'continue's, the shield plate 254 rotates with the dial I245 and wheel 228y until it occupies a position directly under the pawl 227. As soon as this'occurs the pawl-227 is prevented -from engaging the teeth of the ratchet wheel 228 and so the feeding of the wheel 2l is stopped.

The above mechanism is used when the wheel feed is accomplished by power derived from the eccentric or cam '203. When it is desired to, manually adjust the position of the wheel'21 or to feed itduring the grinding operation, it is only necessary to rotate the hand wheel 259 whichgisffastened directly to the shaft 100. A stop 260 is mounted adjacent the dial 245 on ashort shaft 261 so that it maybe swung into or out of operativey position. In Figs. 14 and 16, this stop is shown in operative position while in Fig.

asA

. ali-24,784

15 it is shown swung out of operative position. In itsoperative position, the stop 26() strikes against the abutment 262 formed on the periphery of dial 245 and which thus prevents further manual adjustment of the wheel 21 without first removing the gear 252 from engagement with the ratchet wheel 228. Y

During either hand or power, feeding of the wheel 21', the relative position of the dial 245 and the ratchet wheel 228 may be Varied by rotation of the gear 252. This produces a slight additional rotation of the shaft 100 before the feeding is stopped by action of either of the stops 254 or 260. In this way the operator can, by slight adjustment of gear 252 compensate for the continuous wearing away of the abrasive wheel 21, or for adjusting the feed mechanism to grind to a predetermined size.

The table 12 is surrounded by a suitable yenclosure in order to retain the water lor other liquid used in connection with the grinding. This enclosure comprises a wall 275 partly surrounding the table12 and fastened in any suitable way to the base of the machine. Secured ,to this enclosure 275 b suitable hinges, 2 6, are movable enclosure members 27 7 comopening the movable enclosure members 277 access to the table may be conveniently had to remove or position work to be ground and, with the enclosure members in the position shown they yform a complete enclosure for the table 12 and prevent the water from being thrown from the machine. Pins 277a are provided to retain the movable members 277 in their closed position.

Any suitable ymeans maybe provided for supplying water to the Wheel,21 and table 12, preferably Imount a pump 278 on. the yshaft on which one of the,l idler pulleys 27a is mounted so that the pump may be operated' from the motor 25 whenever the table 12 is being rotated. A suction pipe 279 extends into a-settling tank 280 from which the pump 278 draws the4 water and forces it through pipes 281 to the contacting sur,- faces ofthe Wheel 21 and the work.

On the samev shaft as that on which the pump 278 is mounted'may be provided an electric generator 282 of the direct 'currenttype shown in dotted lines in Fig. 2. This, however, is only-necessary and is only provided when the current available for the motors 1 5 and 25 is alternating. The direct current supplied by generator 282 may be used for energizing the magneticchuck with which the table 12 is equipped. A switch 285 is also provided conveniently mounted on the sideof the column 11 to control the current supplied from generator 282 or other source to operate the magnetic chuck/ which may be mounted on table 12.

one `of which is shown atpleting the enclosure about the table 12. By

shaft,

ing means for said screw What I claim is:

1. A surface grinding machine comprising in combination, a base, table thereon, a vertically mounted wheel spindle, a wheel on said spindle adapted to engage Work on said table, a horizontally mounted motor for rotating said wheel spindle, and driving connections between said motor and spindle comprising a pair of bevel gears and a sliding connection whereby said wheel spindle may be rotatably connected to said motor with maximum flexibility and adjustment. a Y

2. A surface grinding machine comprising in combination, base, a work-carrying table thereon, a vertically mounted wheel spindle, a engage work on said tab e, a horizontally mounted motor for rotating said Wheel Spindle, and driving connections between said motor and spindle including a pair of bevel' gears, a flexible lconnection between said motor and said gears, and a sliding connection between said gears and said spindle whereby said spindle may be rotatably connected to -said motor with maximum flexibility and adjustment.

3. In a grinding machine, the combination of a base, a wheel head on said base, a screw engaging'said wheel head, Said screw adapted to be rotated in either direction to 'vary the position of said wheel head, rotating means for said screw comprising a shaft and a driving connection between said shaft and screw, oppositely rotating pulleys, and means to drive said shaft from either one of said pulleys to rotate said screw in either direction.

4. In a grinding machine, thev combination of y a base, a wheel head on said base, a screw engaging said wheel head, said screw adapted to be rotated in either direction to vary the position of said wheel head, a worm wheel on said screw, a shaft having a worm thereon engaging said worm wheel, a rotatably mounted pulley adjacent'said worm shaft, and driving means to rotate said worm shaft from said pulley.

5. In a grinding machine, the combination of a base, a wheel head on said base, a screw engaging said wheel head, said screw adapted to be rotated in either direction to vvary the position of said wheel head, a worm wheel on said screw, a shaft having a worm thereon engaging said worm wheel, oppositelyrotating pulleys adjacent said worm and ,driving means to rotate said worm shaft from either of said pulleys.

6.vv In'a grinding machine, the combination of a base, a wheel head on said base, a screw engaging Said wheel head, said screw adapted to be rotated in either direction to vary the position of said wheel head, rotatcomprising a shaft and a driving connection between said shaft a work-carrying wheel on saids indle adapted to 'ioo ice

` means to Amanuall vary and screw, oppositely rotating pulleys, and means mounted on' said shaft and adapted 'to contact with one of said pulleys to drive said shaft from Veither of said pulleys and rotate said screw in either direction.

7. 1n a grinding machine, the combination of a base, a wheel head on said base, a screw engaging said wheel head, salti screw adapted to be rotated in either direction to vary the position ofA said wheel head, a worm wheel mounted on said screw, a shaft having a. worm thereon engaging said Worm wheel, oppositely rotating pulleys adjacent said worm shaft, and an eccentrically mounted pulley adapted to frictionally engage either of said first mentioned pulleys.

8. In a grinding machine, the combination of a base, a wheel head on said base,

a screw engaging said wheel head, said screw adapted to be rotated in either direction to vary the position of said wheel head, a Worm wheel mounted on said screw, a shaft having a worm thereon engaging said worm wheel, oppositely rotating pulleys adjacent said Worm shaft, an eccentrically mounted pulley adapted to frictionally eugage either of said first mentioned pulleys, and a connection between said eccentrically mounted pulley and said' worm shaft comprising a pin on said eccentrically mounted pulley and a slotted member on said shaft to drive said shaft from said last mentioned pulley.

9. A surface grindin ing in combination, a ase, a column adjustably mounted thereon, a table rotatably mounted on said base, a Wheel head vertically movable on said column toward or away from said table, a grinding wheel thereon, means. for rotating said table, means operated by said table rotating vmeans to actuate mechanism to feed said Wheel toward said table a predetermined variable amount with each revolution of the table, means to limit the feeding movement of said wheel for each revolution of said table, and the limit of feeding movement of sai wheel.

10. A surface grinding machine comprising in combinatlon, a base, a column adjustably mounted thereon, a table rotatably mounted on said base, a wheel head vertically movable on said column toward or away from said table, a grinding wheel thereon, means for rotating said table, a cam operated b said table rotating means to actuate mec anism to feed said wheel toward said table a predeterminedvariable amount with each revolution of thetable, means to limit the feeding movement of said'wheel for-each revolution of said table` and means to manually vary theI limit of feedin movement of said wheel.

11. surface grinding machine comprismachine comprising in combination, a base, a column adjustably mounted thereon, a table rotatably mounted on said base, a wheel head vertically movable on said column 'toward or away from said table, a grinding wheel thereon, means for rotating said table, a cam operated by said Atable rotating means, means operated by said cam'to feed said wheel toward said table a predetermined variable amount with.

each revolution of the table, means to compensate for ychanges in adjustment of said column, and means to stop the feeding movement of said wheel at any predetermined position. A

t 13. A surface grinding machine comprising in combination, a base, a column adjustably mounted thereon, a table rotatably mounted on said base, a wheel head vertically movable on said column from said table, a grinding wheel thereon, means for rotating said table, a pawl operated by said table rotating means to feed said wheel toward said table a predetermined variable amount with each revolution 0f the table, a ratchet wheel engaged by said pawl, a. dial adjacent said ratchet wheel and means on said dial to stop the. feeding movement of said ratchet wheel at any predetermined position. y

14. A surface grinding machine comprising in combinatlon, a base, a4 column adjustably mounted--thereon, a table rotatably mounted on said base, a wheel head vertically movable on said column toward or away from said table, a grinding wheel thereon, means for rotating said table, a pawl operated by said table rotating means to feed said wheel toward said table a predetermined variable amount with eachrevolution of the table, a ratchet wheel engaged by said pawl, a dial adjacent said ratchet Wheel and normally Arotating therewith, and means mounted on said dial to stop the movement of 'said ratchet wheel at any predetermined posltion.

15.l A surface grinding'machine comprising in combination, a base, a column adjustably mounted thereon, a table rotatablymounted on said base, a wheel head vertically movable on said columnl toward or away from said table, a grinding wheel thereon,

toward or away. 

